Predictors of long-term survival following radical surgery for malignant pleural mesothelioma

Abstract

The aim of radical surgery for malignant pleural mesothelioma (MPM) is to achieve greater survival than from chemotherapy alone. Although adverse overall prognostic factors have already been determined, our aim was to identify the most important factors affecting long-term survival arbitrarily defined as >24 months. We retrospectively reviewed the records of 252 patients (35 females; 193 epithelioid and 59 biphasic; 112 extrapleural pneumonectomy (EPP); 140 extended pleurectomy decortication (EPD)) who survived for at least 90 postoperative days. We tested for factors affecting overall cancer-related mortality and specific clinical factors predicting the 24-month survival. The overall median survival was 18.2 (SE 1.3, 95% CI 15.8-20.7 months). There was no difference in survival between EPP and EPD (P = 0.92). One hundred and twenty-eight patients received induction, adjuvant or palliative chemotherapy. Seventy-seven (30.6%) patients survived for >24 months. On univariate analysis, age at operation over 60 years (P = 0.044), pT4 stage (P = 0.041), any lymph node metastases (P = 0.002), biphasic cell type (P = 0.00) and no administration of chemotherapy (P = 0.00) were associated with decreased survival. On multivariate analysis, age <60 (P = 0.018, OR = 0.7), epithelioid disease (P = 0.001, OR = 0.56) and negative nodes (P = 0.009, OR = 0.67) were associated with increased survival and no administration of chemotherapy (P = 0.00, OR = 1.9) with decreased survival. Factors predicting survival over 24 months included: age at operation under 60 (P = 0.014), epithelioid histology (P ≤ 0.00), negative nodes (P = 0.002) and chemotherapy (P = 0.022). These results support a policy of accurate preoperative tissue diagnosis, nodal staging and induction chemotherapy prior to radical surgery for MPM, which can result in long-term survival. Trials investigating the role of surgery should be focused on confirming and refining these selection criteria.